Deep South Winterwx Discussion 2015-2016

[Brent]

Birmingham:

THIS PERIODS WEATHER IS DOMINATED BY THE APPROACHING UPPER LOW
FROM THE NORTHWEST. THE MODELS ARE ALL IN AGREEMENT TODAY ON THE
TRACK OF THIS FEATURE PASSING OVER THE AREA LATE SATURDAY NIGHT
AND SUNDAY MORNING. ADDITIONALLY...THEY ALL AGREE ON FAIRLY DEEP
MOISTURE AND ENOUGH QPF TO WARRANT A THREAT OF MEASURABLE SNOW
ACROSS CENTRAL ALABAMA. MAIN QUESTION IS THE QPF. I`M PRETTY
CONFIDENT THAT IT IS GOING TO SNOW BUT GROUND TEMPERATURES WILL BE
WARM AND THE INITIAL SNOWFALL SHOULD MELT. HOWEVER...THIS EVENT
COULD LAST UP TO 6 HOURS FOR SOME LOCATIONS AND EVENTUALLY
ACCUMULATIONS WILL OCCUR...PRIMARILY ACROSS THE NORTHERN COUNTIES.

DUE TO THE WIDE RANGING QPF FORECASTS BY GUIDANCE...WILL KEEP SNOW
TOTALS AROUND 1 INCH BUT THERE IS SOME POTENTIAL FOR A HIGHER
TOTAL AND A WATCH OR WARNING FOR HEAVY SNOW MAY BE NEEDED SATURDAY
MORNING. NEEDLESS TO SAY SUNDAY WILL BE COLD AND BREEZY.

[Dionne]

It appears to have come and gone.....we got zip. We needed the rain. It was all north of I-20 and didn't dip south until Alabama. We're at 71F right now. My vegetable garden needed that rain!!

Correction.....ambient is 74.5F right now 5PM CST.

[Brent]

[AL Chili Pepper]

Wow...that looks like a little spot of 4-5" south of Montgomery in what I think is Coffee County! You have to maximize it to see it. According to the discussion I read, the NAM ad been drier than the GFS with the system, but seems to be coming in line with it. The GFS shows a wide area of snow over most of MS and AL in 36 hours.

[Brent]

Birmingham:

ONCE THIS STORM SYSTEM PUSHES OUT...THE NEXT THREAT WILL BE IN THE
FORM OF SNOW. AN UPPER LEVEL DISTURBANCE WILL SLIDE SOUTHEAST INTO
CENTRAL ALABAMA. THIS LOW WILL PROVIDE THE DYNAMIC COOLING THAT
WILL BE NEEDED FOR SNOWFALL ACROSS CENTRAL ALABAMA. BIG QUESTION
ON THIS SYSTEM NOW WILL BE THE EXACT TRACK OF THE UPPER LEVEL
DISTURBANCE AND WHERE THE HEAVIEST BAND OF SNOW WILL SET UP. FOR
NOW WILL GO WITH THE BAND OF HEAVIEST PRECIPITATION GENERALLY
ALONG AND EAST OF THE I-20/59 CORRIDOR FROM MIDNIGHT TO 6 AM
SATURDAY NIGHT...SUNDAY MORNING. AT THIS TIME WILL CONTINUE TO
HIGHLIGHT IN THE HWO AS ACCUMULATIONS ARE EXPECTED TO LESS THAN 2
INCHES WITH THIS SNOW EVENT. MOST OF THE SNOW WILL BE DONE BY NOON
TO 3 PM ACROSS THE SOUTHEASTERN COUNTIES. STAY TUNED FOR FURTHER
UPDATES.

Peachtree City:

FOCUS THEN TURNS TO THE UPPER LOW PROG TO MOVE
ACROSS THE SOUTHEAST U.S. TONIGHT AND SUNDAY...BRINGING DEEPER
MOISTURE BACK ACROSS OUR AREA. BY THIS TIME MODELS SHOW
THICKNESSES COLD ENOUGH FOR SNOW OVER A LARGE PORTION OF THE
COUNTY WARNING AREA. QUESTION THEN BECOMES WILL SNOW BE ABLE TO STICK???
SUSPECT ANY INITIAL SNOW WOULD MELT WITH GROUND STILL RELATIVELY
WARM...BUT GIVEN TIME AND ANY BANDS OF MODERATE SNOW COULD RESULT
IN SOME ACCUMULATIONS...ESPECIALLY IN THE MOUNTAINS. CONFIDENCE
NOT YET THERE THAT WE WILL MEET CRITERIA FOR WINTER STORM
WATCH/WARNING AT THIS TIME...SO WILL HOLD OFF FOR NOW.
HOWEVER...PLAN TO ISSUE A SPECIAL WEATHER STATEMENT EMPHASIZING
SNOW THREAT. SUSPECT AT SOME POINT WILL HAVE TO GO WITH AT LEAST
AN ADVISORY FOR SOME PORTION OF THE COUNTY WARNING AREA. TO
COMPLICATE MATTERS EVEN MORE...WINDY CONDITIONS LOOK LIKE A GOOD
BET SUNDAY. WIND ADVISORY WILL PROBABLY BE POSTED FOR MUCH OF THE
COUNTY WARNING AREA WITH HIGH WIND WARNING POSSIBLY IN THE
MOUNTAINS. MODELS SHOW UPPER LOW SHIFTING EAST INTO THE CAROLINAS
SUNDAY NIGHT...THEN MOVING OFF THE MID ATLANTIC COAST BY EARLY
MONDAY...TAKING DEEPER MOISTURE WITH IT.

[Dionne]

It appears to have come and gone.....we got zip. We needed the rain. It was all north of I-20 and didn't dip south until Alabama. We're at 71F right now. My vegetable garden needed that rain!!

Correction.....ambient is 74.5F right now 5PM CST.

All the winter weather remains north of I-20. The northern 1/3 of Mississippi is under numerous warnings and advisories......pinks and blues and greens and reds.....(NWS colors). Temp here is 50.7F and falling.......we had our high for the day at 12:01 AM.

[Stormcenter]

This is from the NWS out New Orleans, LA discussion this morning.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
709 AM CST SAT FEB 28 2009

SHORT TERM...
SEVERAL ITEMS TO TALK ABOUT WITH THIS SYSTEM. FIRST THING NOTICED
IS THE STACKED LOW OVER NEB/KAN. SHALLOW THICKNESSES ARE QUITE
BROAD ASSOCIATED WITH THIS LOW AND WILL QUICKLY MOVE INTO AND OUT
OF THE SOUTHEASTERN CONUS. WEAK CYCLICAL VORTS WILL MOVE AROUND
WHILE MOISTURE IS ALSO DISPLACED TO THE SOUTH OF THE LOW BY
TONIGHT. DEEP COLD AIR AND SOME LOW LEVEL MOISTURE WILL PROVIDE A
20% CHANCE OF SEEING SOME FLURRIES OVERNIGHT TONIGHT. WENT WITH
FLURRIES SINCE MOISTURE IS LIMITED. HERE ARE THE THICKNESS
BREAKDOWNS.

WHAT WE LIKE TO SEE IN LAYER THICKNESSES FOR ONLY SNOW...THESE ARE
NORMALLY ROUNDED:
1000-850MB LAYER 1300M DEEP OR LESS
1000-700MB LAYER 2810M DEEP OR LESS
1000-500MB LAYER 5370M DEEP OR LESS
850-700MB LAYER 1530M DEEP OR LESS
850-500MB LAYER 4050M DEEP OR LESS

TO GET OTHER PRECIP TYPES OR A MIXTURE...WE WOULD LOOK AT THESE
THICKNESSES FOR SLIGHTLY DIFFERENT VALUES. THE THERMAL PROPERTIES
CHANGE ABRUPTLY AS THE STACKED LOW SKIRTS THE AREA CAUSING ANY
LIGHT RAIN TO CHANGE IMMEDIATELY TO SNOW. THIS WILL BE SEEN EVEN
BETTER TO THE NORTH AND EAST OF THIS AREA WHERE MODERATE SNOW IS
EXPECTED. COULD HAVE EASILY BROUGHT FLURRIES INTO A FEW MORE
COUNTIES AND PARISHES BUT WOULD LIKE TO SHOW MORE OF A TREND
BEFORE INCLUDING MORE AREAS. AS THE 12Z RUNS COME IN AND SHOW
THE SAME SCENARIO...MORE AREAS CAN BE COMMITTED. MAV NUMBERS ARE
CREEPING UPWARD FOR THE MCB AREA TO SEE FLURRIES AND THE ROS IS
NOW SHOWING -SN AROUND 9Z IN THE MORNING. ONLY FLURRIES ARE
EXPECTED WITH NO ACCUMULATIONS.

[Brent]

12z GFS and NAM both look GREAT:

GFS:









NAM:









*dies*



*dies again*

Before you hyperventilate, remember, this is model output only. I do believe somebody could see 5 inches of snow across a very narrow area, but I maintain we won’t know that “magic spot” until the the event begins and the heaviest snow band sets up tonight. There is very limited skill in forecasting snow placement and amounts with a cold core upper low in Alabama.

The GFS is also similar, although I don’t have the accumulated snow chart at this point.

We do note the ground is warm, but you can’t ignore what we see to the northwest…

500 mb heights are down to 5430 meters near Wichita, and bands of heavy snow are setting up underneath the ULL.

Seems like a pretty good chance much of North/Central Alabama will potential for 1 to 2 inches of snow, with isolated amounts to 5 inches in a very narrow band. The NWS, most likely, will issue a winter weather advisory, or maybe even a winter storm watch, by late morning.

http://www.alabamawx.com/?p=15927

[Ed Mahmoud]

New WRF has Atlanta with happy heights and 850 mb temps for snow, but looking at AccuWx PPV 2 meter temps, awfully marginal. About 3ºC, 37 or 38ºF. For ballpark 8 inches plus of snow if all works perfectly. Rain/accumulating slush line could wind up near ATL.


Penn State U e-Wall has a regional NAM floater over the Southeast, so for the next 20 hours or so, you can track both the surface temps and 850 mb temps over your favorite city in the Southeast.

Down to 57ºF with winds gusting to 29 mph in the largest modern city in the old CSA, Houston, Texas.

[DESTRUCTION5]

Well Brent if you dont get snow in that setup you may as well pack it in and join Luis on the countdown thread to june 1st...LMAO

[Ivanhater]

Chance of Snow in the Pensacola area Sunday morning!

Sunday: A slight chance of rain and snow before 9am. Partly cloudy, with a high near 54. Windy, with a northwest wind between 20 and 25 mph, with gusts as high as 35 mph. Chance of precipitation is 20%.

[cycloneye]

Well Brent if you dont get snow in that setup you may as well pack it in and join Luis on the countdown thread to june 1st...LMAO

Or Brent,you may want to think already what numbers you will have for the Hurricane season from tommorow.

[Dave]

Pushing snow towards Brent...maybe...

[Brent]

Well Brent if you dont get snow in that setup you may as well pack it in and join Luis on the countdown thread to june 1st...LMAO

Don't worry, I will. Winter is over for me after this event regardless of what happens. Hard to believe it's going to snow, 60 degrees and sunny right now, which is why I'm still trying hard to remain cautious.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PEACHTREE CITY GA
1000 AM EST SAT FEB 28 2009

GAZ001>009-011>016-019>025-027-030>039-041>062-066>076-078>086-
089>098-102>113-010200-
DADE-WALKER-CATOOSA-WHITFIELD-MURRAY-FANNIN-GILMER-UNION-TOWNS-
CHATTOOGA-GORDON-PICKENS-DAWSON-LUMPKIN-WHITE-FLOYD-BARTOW-
CHEROKEE-FORSYTH-HALL-BANKS-JACKSON-MADISON-POLK-PAULDING-COBB-
NORTH FULTON-GWINNETT-BARROW-CLARKE-OCONEE-OGLETHORPE-WILKES-
HARALSON-CARROLL-DOUGLAS-SOUTH FULTON-DEKALB-ROCKDALE-WALTON-
NEWTON-MORGAN-GREENE-TALIAFERRO-HEARD-COWETA-FAYETTE-CLAYTON-
SPALDING-HENRY-BUTTS-JASPER-PUTNAM-HANCOCK-WARREN-TROUP-
MERIWETHER-PIKE-UPSON-LAMAR-MONROE-JONES-BALDWIN-WASHINGTON-
GLASCOCK-JEFFERSON-HARRIS-TALBOT-TAYLOR-CRAWFORD-BIBB-TWIGGS-
WILKINSON-JOHNSON-EMANUEL-MUSCOGEE-CHATTAHOOCHEE-MARION-SCHLEY-
MACON-PEACH-HOUSTON-BLECKLEY-LAURENS-TREUTLEN-STEWART-WEBSTER-
SUMTER-DOOLY-CRISP-PULASKI-WILCOX-DODGE-TELFAIR-WHEELER-
MONTGOMERY-TOOMBS-
1000 AM EST SAT FEB 28 2009

...ACCUMULATING SNOW POSSIBLE OVER MUCH OF NORTH AND CENTRAL
GEORGIA SUNDAY...

A STRONG UPPER LEVEL STORM SYSTEM WILL MOVE ACROSS CENTRAL AND SOUTH
GEORGIA LATE TONIGHT AND SUNDAY...THEN EXIT OFF THE SOUTH CAROLINA
COAST SUNDAY NIGHT.

THIS SYSTEM IS EXPECTED TO SPREAD PRECIPITATION ACROSS NORTH AND
CENTRAL GEORGIA...BEGINNING AS LIGHT RAIN TONIGHT IN NORTHWEST
GEORGIA...AND THEN BECOMING A MIX OF RAIN AND SNOW LATE TONIGHT OVER
WESTERN GEORGIA BEFORE CHANGING TO ALL SNOW FROM WEST TO EAST. THE
COLDEST AIR ALOFT AND NEAR THE SURFACE APPEARS LIKELY TO SHIFT INTO
CENTRAL GEORGIA BEFORE PARTS OF NORTH AND NORTHEAST GEORGIA...CLOSER
TO THE TRACK OF THE CENTER OF THE UPPER LEVEL LOW STORM SYSTEM.
THEREFORE...AREAS NEAR COLUMBUS AND AMERICUS COULD SEE A SWITCH TO
SNOW BEFORE AREAS NORTH AND NORTHEAST OF ATLANTA.

UNCERTAINTY STILL REMAINS CONCERNING ACCUMULATIONS. WITH THE GROUND
STILL RELATIVELY WARM AND THE SNOW MELTING AS IT FALLS INTO THE
WARMER AIR NEAR THE GROUND...ANY SNOW THAT FALLS INITIALLY SHOULD
MELT. TEMPERATURES AT THE SURFACE ARE EXPECTED TO BE IN THE MID AND
UPPER 30S OVER MUCH OF NORTH GEORGIA AND IN THE LOW 40S OVER AREAS
SOUTH AND EAST OF MACON. HOWEVER...AS THE COLDER AIR PRESSES EAST
AND SOUTH DURING THE DAY...BANDS OF MODERATE SNOW COULD RESULT IN
LIGHT ACCUMULATIONS ACROSS MUCH OF NORTH AND CENTRAL GEORGIA.

AREAS NORTH AND WEST OF A CORDELE TO LOUISVILLE LINE COULD SEE
ACCUMULATIONS AROUND AN INCH BY SUNDAY EVENING. MOST OF THE
ACCUMULATION SHOULD BE CONFINED TO GRASSY AND ELEVATED ROAD SURFACES
SUCH AS BRIDGES AND OVERPASSES. HOWEVER...IF PERIODS OF HEAVY SNOW
OCCUR...ISOLATED ACCUMULATIONS OF 1 TO 3 INCHES COULD FALL ON
ROADWAYS. AREAS SOUTH OF THE CORDELE TO LOUISVILLE LINE WILL SEE
LITTLE OR NO ACCUMULATIONS WHERE TEMPERATURES REMAIN IN THE UPPER
30S.

PLEASE STAY TUNED TO NOAA WEATHER RADIO...OR YOUR FAVORITE TELEVISION
OR RADIO STATION...FOR LATER STATEMENTS AND POSSIBLE WARNINGS OR
ADVISORIES ON THIS WINTER WEATHER SITUATION.

[AirNik]

Not getting my hopes up but interesting nonetheless.

[Brent]

This will be epic IF this verifies. 6 inches easily, and that's showing a large area with close to an inch of QPF and even one area of 1.5 inches.





If these models are even close to right a lot of people are going to be shocked. NWS Birmingham is still saying an inch at best.

[MGC]

Who knows, this might turn out to be another Dec 11 (New Orleans snow) snow event for Alabama and parts of Georgia and perhaps even NW Florida if the ULL tracks as predicted....Hope Ya'll get some white stuff....MGC

[Ed Mahmoud]

Joy making Upper Low- all snow at reporting stations around Springfield where it is precip'ing, (well, a couple of ASOS reporting "mist", but at 28 and 30ºF, I don't think so)



Sorry Texas is missing out, but this is like the December 10 Houston Miracle Upper Low of Joy.


She is beauty, no?

[Dave]

MESOSCALE DISCUSSION 0175
NWS STORM PREDICTION CENTER NORMAN OK
1147 AM CST SAT FEB 28 2009

AREAS AFFECTED...SERN MO...NERN AR...WRN TN/KY

CONCERNING...HEAVY SNOW

VALID 281747Z - 282145Z

MODERATE TO HEAVY SNOW HAS OCCASIONALLY BEEN OBSERVED ACROSS S CNTRL
MO OVER THE PAST FEW HOURS...WITH A RECENT REPORT OF 2 INCHES AN
HOUR AT FT WOOD. ANTICIPATE THIS TREND TO CONTINUE ESEWD TOWARD SERN
MO...NERN AR...AND WRN TN/KY. RATES OF NEAR 1 TO 2 INCHES AN HOUR
CAN BE EXPECTED IN HEAVIER SNOWFALL IN ADDITION TO RESTRICTED
VISIBILITIES.

A VIGOROUS UPPER LOW...CURRENTLY LOCATED OVER ERN KS...WILL QUICKLY
DIVE SEWD REACHING CNTRL AR BY 00Z. AT THE SURFACE...STRONG ARCTIC
HIGH PRESSURE IS QUICKLY BUILDING ACROSS THE CNTRL STATES...AND
SUBFREEZING TEMPERATURES WILL REMAIN ACROSS THE OUTLINE AREA WHILE
AREAS TO THE SOUTH AND EAST WILL QUICKLY COOL THROUGH THE AFTERNOON
IN STRONG COLD AIR ADVECTION. A NW TO SE ORIENTED BAND OF MDT/HVY
SNOW IS OCCURRING AHEAD OF THE UPPER LOW...WITH ADDITIONAL
DEVELOPMENT BEGINNING INTO SERN MO...WRN KY/TN...AND NERN AR ALONG
AN INVERTED SURFACE TROUGH AXIS AND IN CONJUNCTION WITH STRONG UPPER
DIVERGENCE/FAVORABLE JET DYNAMICS. SUBTLE ISENTROPIC LIFT IS
CONTRIBUTING AS WELL...WITH RELATIVE WARM/MOIST AIR TO THE EAST
BEING DRAWN ATOP THE ARCTIC AIRMASS/SUBFREEZING TEMPERATURES TO THE
WEST. THIS IS REFLECTED WELL IN RECENT PADUCAH VAD WIND PROFILES.
12Z SPRINGFIELD SOUNDING SHOWS SATURATED COLUMN GENERALLY FROM THE
SURFACE THROUGH 500 MB...AND MODEL SOUNDINGS ARE INDICATIVE THAT
AREAS IMMEDIATELY DOWNSTREAM WILL REMAIN SATURATED AS
WELL...PROMOTING MDT/HVY SNOW. EXPECT THIS TREND TO GENERALLY SHIFT
ESEWD IN CONJUNCTION WITH THE MOVEMENT OF THE UPPER LOW.

..HURLBUT.. 02/28/2009

http://www.spc.noaa.gov/products/md/md0175.html

[Ed Mahmoud]

My wife thinks I'm nutty getting excited about snowstorms in the Northeast or Southeast. The Northeast, I lived there, the Southeast, rare and unusual factor.

Snow in Minnesota- supposed to happen.


But anyway, it is like a hurricane, missed school, big weather event, but if people stay off the roads, injuries should be minimal. The snow is gone, especially in March, in the South, in a day, no blue tarps, no destroyed Popo's beach house in Galveston where we enjoyed all our warm season holidays.

I do feel bad for people that can't take a day off, doctors, cops, etc., and have to risk the roads. I hope they remember to drive slowly and with caution.


I still have warm memories for the cancelled Atlanta NASCAR race that was called on account of snow back 16 years ago...